Apparatus unit



W. E. BOOTH.

APPARATUS UNIT.

APPLICATION FILED APR. I7. 1918.

1,324,792. Patented Dec. 16,1919

UNITED STATES PATENT OFFICE.

WIIiFRED E. BOOTH, OF NEW YORK, N. Y.. ASSIGNOR TO WESTE'RN ELECTRIC COMPANY,

INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

APPARATUS UNIT.

To all whom it may concern:

Be it known that I, \VILFREI) E. BooTir, a citizen of the United States, residing at New York; in the county of New York and State of New York, have invented certain new and useful Improvements in Apparatus Units, of which the following is a full, clear, concise. and exact description.

This invention relates to apparatus units and more in particular to an apparatus unit combining a resistance element and a ca- I which is of pacity element.

In the electrical field there is a considerable demand for a resistance unit combined with an electrostatic capacity of a certain fixed value. Particularly is this true in connection with radip transmission where the circuit conditions often necessitate the employment of leakage resistances, usually of high value, shunted or connected in series with a'capacity of a certain fixed value.

In many cases wh ere such units are used, it

is advantageous to avoid the complication of wiring connections by employing combined units. Again, such an arrangement provides more compact apparatus, a feature decided importance as, for example, in connection with radio sets for use on aeroplanes, where the space available for mounting the apparatus is very limited.

The object of the present invention therefore is to provide a combined capacity and resistance unit which will occupy as little space as possible, and one in which the amount of wiring necessary will be reduced to a minimum.

Further objects are to provide a unit of the above type which will be cheap to manufacture, easily 1nounted,an .l one in which the electrical constants will not be appreciably affected by exposure ordinarily met with under service conditions.

Therefore, in accordance with this invention, there is provided a unit in which the capacity element is wound about the resistance element and in which the mount ing lugs are also employed as terminals for the making of the necessary circuit connections. As a protection against mechanical injury and also to preclude the possibility of the electrical constants of the unit being affected by moisture, etc, the entire unit is given a heavy coating of an insulating com pound.

The various features of the invention may Specification of Letters Patent. Patented Dec, 16, 1919 Application filed April 17, 1918. Serial No. 229,067.

be more clearly understood by referring to the accompanying drawing in which Figure l is a view partly in section showing a unit embodying this invention and having the resistance element connected in series with the capacity element; Fig. 2 is an end view of the unit shown in Fig. 1; Fig. 3 shows the manner in which the strips of conducting and non-conducting material are laid together to form the capacity element; Fig. 4 shows diagrammatically a unit of the proposed type in which the capacity element is connected in parallel with the resistance element; Fig. 5 shows a like unit in which the two elements are connected in series; and Fig. 6 shows diagrammatically a unit in which the resistance element is shunted by a pair of capacity elements connected in series.

Referring now more particularly to F igs. l, 2, 3 and 5, there is shown a resistance element 7 which, in the present case, consists of a rod of carbon or similar material, although other types of resistance elements fitted with suitable terminals might be employed equally well. When rods of carbon or graphite are used, it has been found preferable to copper-plate the ends in order to facilitate the making of the necessary connections and also to prevent any disturbing microphonic action: About the resistance element 7 is wound the capacity element 8, consisting of alternate strips of metal foil 99 and insulating material such as sheets of paper 10-10. These strips are laid together as shown in Fig. 3 and are then wound about the resistance element in the well-known manner as employed in condenser construction, the lengths of foil being such as to give the desired capacity. A terminal 11 of metal foil is provided for each conducting sheet as a means for making the necessary connections. After the capacity element is wound it is held in place by tying and is then impregnated in melted paraffin or some similar material to exclude all moisture. The terminal punchings 12-12 are then slipped over the end of the resistance element to which they are securely soldered, one of the capacity terminals being connected to one of the terminal punchings by the same operation. The other capacity terminal is connected to an additional connecting terminal 13, after which the entire unit is covered with a heavy coating of asphaltic material 14. The terminals 12 are provided at one end with an open coil 15 adapted to spring over the ends of the resistance element, and at the other end with a soldering lug 16 adapted to serve as a connecting terminal. These terminals are. also provided with perforations to receive the mounting screws 17-17 by which the unit is mounted upon the insulating base 18. When it is desired to provide a unit in which the resistance element is shunted by the capacity element, the capacity terminals are connected directly to the line terminal punchings 12-12, as shown diagrammatically in Fig. 4. In Fig. 6 is sllOWIl diagrammatically the circuit connections when it is desired to shunt the resistance with a pair of capacity elements connected in series. In this case, one terminal of each capacity element is connected to a line punching 12 as shown, and the other terminals of the capacity elements are joined together by soldering to the terminal 13.

Although in the structure illustrated the capacity element is described as being wound directly upon the resistance element, there are certain conditions under which it has been found advantageous to wind the capacity element upon a mandrel and then, after it has been impregnated, slip it over the resistance element with which it is to be associated. Such an arrangement facilitates the repair of units in which one of the elements has become defective and makes possible the interchangeability of parts. Again, th capacity element may be completely inused in a tubular casing provided with a. hollow core into which the resistance element ma be inserted.

What IS claimed is:

1. An apparatus unit comprising a solid core of resistance material, a capacity element wound upon said core, and a pair of conducting lugs attached to the ends of said core and adapted to serve both as mounting supports and terminal connectors for the unit.

'2. An apparatus unit comprising a cylindrical carbon resistance element, a plurality of sheets of conducting material separated by sheets of nouconducting material wrapped about said resistance element and connected thereto, connecting terminals for said resistance element, and a shell of insulating material completely surrounding said resistance and capacity elements.

3. An apparatus unit comprising a resistance elen ent. a capacity element wound upon said resistance element and connected thereto, and means for mounting said unit, said mounting means being in direct electrical connection with the terminals of said resistance element.

In witness whereof I hereunto Subscribe my name this 29th day of March, A. 1)., 1918.

WILFRED E. BOOTH. 

